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Varnish

Seal your external wooden doors, windows, frames, and other joinery with wood varnish; we stock the biggest and most trusted brands in exterior wood varnishes including Coo-Var, Blackfriar, Bonda, and Flag.

The best exterior wood varnishes provide excellent UV resistance and waterproofing to joinery such as doors and windows, protecting wood from extreme climatic conditions. They help prevent swelling and cracking, increasing the life of wood, saving you money from replacing parts or entire door and window frames.

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Coo-Var Yacht & Seaplane Varnish

Coo-Var Yacht and Seaplane Varnish is a traditional marine quality UV resistant varnish. Coo-Var Yacht and Seaplane Varnish can be used over existing paintwork to increase gloss finish and weather resistance. Woodwork Doors Gates Facias Wooden garage doors For interior or exterior use Available in sizes from 250ml up to 5L (gloss),...

Price £5.55
In stock

Bonda Marine Wood Seal

Bonda Marine Wood Seal is a durable, single component polyurethane sealer which can be applied to all woods and concrete to leave a non-porous finish. Tough yet flexible, and has excellent adhesion to many woods Non-Yellowing High Gloss Clear More Information **Available for delivery - see Delivery Options below**

Price £10.73
In stock

Blackfriar Exterior Varnish

This product is temporarily unavailable; in the meantime, our technical team recommend Coo-Var Yacht & Seaplane Varnish as a great alternative - use discount code SAVE10 at checkout to save 10%! Please note: it is important to check that any alternative product is suitable for your requirements, as our suggestion is given in good faith...

Price £20.60
In stock

Blackfriar Super Yacht Varnish

This product is temporarily unavailable; in the meantime, our technical team recommend Coo-Var Yacht & Seaplane Varnish as a great alternative - use discount code SAVE10 at checkout to save 10%! Please note: it is important to check that any alternative product is suitable for your requirements, as our suggestion is given in good faith...

Price £20.60
In stock

Flag Yacht Varnish

Flag Yacht Varnish is a highly durable exterior gloss varnish which has good weathering and UV resistance, which provides a tough and flexible finish.  For use on exterior wood  Suitable for marine applications, also doors, window frames, furniture and floors Non-yellowing - Excellent coverage - Based on premium quality resins Please...

Price £10.14
In stock

Tikkurila Merit Jahti 20

Merit Jahti 20 is a one-component urethane-alkyd semi-matt lacquer recommended for boats, floors, doors, windows, and other wooden surfaces both indoors and outdoors. Excellent resistance to abrasion Contains UV-protective agent Excellent resistance to all ordinary cleaning detergents, SFS 3755 Good resistance to solvents, e.g. gasoline,...

In stock

Tikkurila Merit Jahti 80

Merit Jahti 80 is a one-component urethane-alkyd gloss lacquer recommended for boats, floors, doors, windows, and other wooden surfaces both indoors and outdoors. Excellent resistance to abrasion Contains UV-protective agent Excellent resistance to all ordinary cleaning detergents, SFS 3755 Good resistance to solvents, e.g. gasoline,...

In stock

Tikkurila Pinjalac HB

Tikkurila Pinjalac HB, a flexible exterior lacquer for window frames, front doors and other wooden surfaces outdoors. Water-bourne actylate Good exterior durability Very clear and transparent lacquer film Thixotropic and easy to spray Elastic but still fast drying Good non-blocking properties For industrial and professional use only...

In stock

Tikkurila Akvilac FD-J 25 - TCW

Tikkurila Akvilac FD-J 25 - TCW is a very fast drying and economical all-round lacquer for interior use. Suitable for joinery industry such as mouldings, panels, doors and other wooden surfaces. Especially suitable for fast production lines. Water-borne, one-component Transparent - can be used on top of dark stain colours Excellent...

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How do you varnish an exterior door?

Preparation is always key to varnishing wooden doors; following proper technique provides the best protection for your exterior wooden door. The surface should be clean, dry, sound and free from contaminants such as oils and waxes. Bare woods should be sanded to provide a key for the varnish - always sand in the direction of the grain! Remove all loose, flaking material, and treat bare areas as new a substrate.

Varnish is applied evenly using light strokes following the grain of the wood; for best results multiple coats may be required, especially on new wood. Brushing well into joints and end grains will help prevent moisture ingress.

Previously varnished surfaces can be stripped back easily using a varnish remover. Always read the data sheets for each product, following manufacturer application instructions.

Can I varnish over exterior stain?

You can varnish over stained wood surfaces - we recommend testing a small patch first to ensure compatibility, or contact our technical team for advice. The first coat of varnish must be applied carefully.

How do you protect exterior wood windows?

Wood varnishes and wood sealers help protect exterior wood window frames from rotting, as well as protected from the damaging effects of UV light and climatic conditions.

How do you varnish a window frame?

The same preparation rules apply to windows frames they do doors, removing contaminants and ensuring a smooth and sound surface on which to varnish. Cracked and weathered window frames can be filled and sanded appropriately - ideal if you've bought a new home or business, inheriting woodwork that hasn't been looked after properly.

Always read the data sheets for each product, following manufacturer application instructions. Follow the grain of the wood when applying varnish by brush or roller. Prior to application of the final coat (or if the overcoating time is exceeded), lightly abrade with fine glass paper, again working with the grain, and remove dust. You may also want to apply a bead of clear caulk to sashes, along the seam between the glass and the wood.